U.S. patent application number 16/646133 was filed with the patent office on 2021-07-22 for flexible body and method for controlling flexible body to deform.
The applicant listed for this patent is BOE TECHNOLOGY GROUP CO., LTD., FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.. Invention is credited to Ting Chen, Song Hu, Jie Huang, Junxiang Lu, Xiaowu Sun, Jianshu Wang, Yajiao Zhang, Peitao Zhu.
Application Number | 20210226117 16/646133 |
Document ID | / |
Family ID | 1000005563402 |
Filed Date | 2021-07-22 |
United States Patent
Application |
20210226117 |
Kind Code |
A1 |
Sun; Xiaowu ; et
al. |
July 22, 2021 |
FLEXIBLE BODY AND METHOD FOR CONTROLLING FLEXIBLE BODY TO
DEFORM
Abstract
Provided are a flexible body and a method for controlling the
flexible body to deform. The flexible body comprises one or more
flexible units, wherein each of the flexible units comprises: a
first electrode, a second electrode, an electroactive polymer
layer, and a thin film transistor, wherein a source electrode or a
drain electrode of the thin film transistor is electrically
connected to the second electrode. The first electrode and the
second electrode are configured to provide an electric field acting
on the electroactive polymer layer, and the electroactive polymer
layer is configured to deform in response to the electric field
provided by the first electrode and the second electrode.
Inventors: |
Sun; Xiaowu; (Beijing,
CN) ; Lu; Junxiang; (Beijing, CN) ; Huang;
Jie; (Beijing, CN) ; Wang; Jianshu; (Beijing,
CN) ; Zhu; Peitao; (Beijing, CN) ; Zhang;
Yajiao; (Beijing, CN) ; Chen; Ting; (Beijing,
CN) ; Hu; Song; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.
BOE TECHNOLOGY GROUP CO., LTD. |
Fuzhou
Beijing |
|
CN
CN |
|
|
Family ID: |
1000005563402 |
Appl. No.: |
16/646133 |
Filed: |
September 27, 2019 |
PCT Filed: |
September 27, 2019 |
PCT NO: |
PCT/CN2019/108738 |
371 Date: |
March 10, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 41/09 20130101;
H01L 27/20 20130101; H01L 41/193 20130101; H01L 41/042 20130101;
H02N 2/0075 20130101 |
International
Class: |
H01L 41/193 20060101
H01L041/193; H01L 41/09 20060101 H01L041/09; H01L 27/20 20060101
H01L027/20; H01L 41/04 20060101 H01L041/04; H02N 2/00 20060101
H02N002/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 2, 2019 |
CN |
201910001040.0 |
Claims
1. A flexible body comprising one or more flexible units, wherein
each of the flexible units comprises: a first electrode, a second
electrode, an electroactive polymer layer, and a thin film
transistor, wherein a source electrode or a drain electrode of the
thin film transistor is electrically connected to the second
electrode; wherein the first electrode and the second electrode are
configured to provide an electric field acting on the electroactive
polymer layer, and the electroactive polymer layer is configured to
deform in response to the electric field provided by the first
electrode and the second electrode.
2. The flexible body according to claim 1, wherein the first
electrode and the second electrode are respectively arranged on
opposite sides of the electroactive polymer layer, or the first
electrode and the second electrode are arranged on the same side of
the electroactive polymer layer.
3. The flexible body according to claim 1, wherein the
electroactive polymer layer comprises an electron-type
electroactive polymer or an ion-type electroactive polymer.
4. The flexible body according to claim 1, wherein the
electroactive polymer layer comprises an ion-type electroactive
polymer, and the flexible unit further comprises an electrolyte
solution layer in contact with the electroactive polymer layer.
5. The flexible body according to claim 4, wherein the
electroactive polymer layer comprises N electroactive polymer
sub-layers, the electrolyte solution layer comprises N-1
electrolyte solution sub-layers, and each of the electrolyte
solution sub-layers is arranged between two adjacent electroactive
polymer sub-layers, wherein N is an integer greater than 1.
6. The flexible body according to claim 4, wherein the
electroactive polymer layer comprises M electroactive polymer
sub-layers, the electrolyte solution layer comprises M or M+1
electrolyte solution sub-layers, and the electrolyte solution
sub-layers and the electroactive polymer sub-layers are alternately
arranged, wherein M is a positive integer.
7. The flexible body according to claim 1, wherein the
electroactive polymer layer comprises an ion-type electroactive
polymer and is doped with a movable anion.
8. The flexible body according to claim 1, wherein the flexible
unit further comprises a first insulating layer overlaying the thin
film transistor, wherein the second electrode is formed on a side
of the first insulating layer away from the thin film transistor,
the first insulating layer is provided with a via hole, and the
source electrode or drain electrode of the thin film transistor is
electrically connected to the second electrode through the via
hole.
9. The flexible body according to claim 1, wherein the flexible
unit comprises a thin film transistor array composed of a plurality
of thin film transistors, a second electrode array composed of a
plurality of second electrodes, and one or more first electrodes,
wherein a source electrode or a drain electrode of each thin film
transistor in the thin film transistor array is electrically
connected to one respective second electrode in the second
electrode array, and the plurality of second electrodes in the
second electrode array are arranged separately and respectively
corresponding to different positions of the electroactive polymer
layer.
10. The flexible body according to claim 9, wherein one first
electrode together with at least two second electrodes provides an
electric field acting on the electroactive polymer layer.
11. The flexible body according to claim 10, wherein the flexible
unit further comprises a data voltage generator configured to be
electrically connected to the source electrodes or drain electrodes
of the plurality of thin film transistors in the thin film
transistor array to provide different first voltages to the second
electrodes.
12. The flexible body according to claim 1, wherein the flexible
body comprises a plurality of flexible units arranged along an
extending direction of the electroactive polymer layer.
13. The flexible body according to claim 12, wherein the first
electrode is a common electrode.
14. The flexible body according to claim 1, wherein the flexible
body comprises a plurality of flexible units arranged in lamination
in a direction perpendicular to an extending direction of the
electroactive polymer layer.
15. The flexible body according to claim 1 configured for use in an
artificial muscle, an artificial limb, a massage chair, or a
transmitter.
16. A method for controlling the flexible body according to claim 1
to deform, comprising: applying a first voltage to the source
electrode or drain electrode of the thin film transistor; applying
a second voltage to the first electrode; and changing the first
voltage to modulate the electric field acting on the electroactive
polymer layer, thereby controlling the flexible body to deform
accordingly.
17. The method according to claim 16, wherein the flexible unit
comprises a thin film transistor array composed of a plurality of
thin film transistors, a second electrode array composed of a
plurality of second electrodes, one or more first electrodes, and a
data voltage generator electrically connected to the source
electrodes or drain electrodes of the plurality of thin film
transistors in the thin film transistor array, and the method
comprises: providing different first voltages to the plurality of
thin film transistors by the data voltage generator; applying the
second voltage to the one or more first electrodes; and changing
the first voltage provided by the data voltage generator to
modulate the electric field acting on the electroactive polymer
layer, thereby controlling the flexible body to deform
accordingly.
18. The flexible body according to claim 16, wherein the flexible
body comprises a plurality of flexible units, and the method
comprises: providing different first voltages to the thin film
transistors in one respective flexible unit by a plurality of data
voltage generators respectively; applying the second voltage to the
first electrode; and changing the first voltages provided by the
plurality of data voltage generators to modulate the electric field
acting on the electroactive polymer layer, thereby controlling the
flexible body to deform accordingly.
19. The method according to claim 16, wherein the deformation of
the flexible body comprises expansion and shrinkage.
20. The flexible body according to claim 13, wherein the flexible
unit further comprises a common electrode wire on the same side as
the thin film transistor, and the common electrode wire is
connected to the common electrode through a conductive adhesive.
Description
CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] The present application is a Section 371 National Stage
Application of International Application No. PCT/CN2019/108738,
filed Sep. 27, 2019, entitled "FLEXIBLE BODY AND METHOD FOR
CONTROLLING FLEXIBLE BODY TO DEFORM", which claims a priority to
Chinese Patent Application No. 201910001040.0, filed on Jan. 2,
2019, with a title of "Flexible body and method for controlling
flexible body to deform", the entirety of which is incorporated
herein by reference.
TECHNICAL FIELD
[0002] The present application relates to a flexible body and a
method for controlling the flexible body to deform.
BACKGROUND
[0003] In recent years, artificial intelligence becomes a focus of
science and technology worldwide. Various new robots based on the
artificial intelligence technology are developed continuously and
widely used in industrial production and daily life. In order to
realize a function of walking or local deformation, current robots
and other similar electrical devices generally need to use an
artificial muscle, and thus a motor or a hydraulic system is
required for control. However, the motor or hydraulic system will
cause the whole system to be relatively cumbersome, thereby
limiting the flexibility, strength and overall working
performance.
SUMMARY
[0004] Embodiments of the present disclosure provide a flexible
body comprising one or more flexible units. Each of the flexible
units comprises: a first electrode, a second electrode, an
electroactive polymer layer, and a thin film transistor. A source
electrode or a drain electrode of the thin film transistor is
electrically connected to the second electrode. The first electrode
and the second electrode are configured to provide an electric
field acting on the electroactive polymer layer, and the
electroactive polymer layer is configured to deform in response to
the electric field provided by the first electrode and the second
electrode.
[0005] According to some embodiments of the present disclosure, the
first electrode and the second electrode are respectively arranged
on either side of the electroactive polymer layer, or the first
electrode and the second electrode are arranged on the same side of
the electroactive polymer layer.
[0006] According to some embodiments of the present disclosure, the
electroactive polymer layer comprises an electron-type
electroactive polymer or an ion-type electroactive polymer.
[0007] According to some embodiments of the present disclosure, the
electroactive polymer layer comprises an ion-type electroactive
polymer, and the flexible unit further comprises an electrolyte
solution layer in contact with the electroactive polymer layer.
[0008] According to some embodiments of the present disclosure, the
electroactive polymer layer comprises N electroactive polymer
sub-layers, the electrolyte solution layer comprises N-1
electrolyte solution sub-layers, and each of the electrolyte
solution sub-layers is arranged between two adjacent electroactive
polymer sub-layers, wherein N is an integer greater than 1.
[0009] According to some embodiments of the present disclosure, the
electroactive polymer layer comprises M electroactive polymer
sub-layers, the electrolyte solution layer comprises M or M+1
electrolyte solution sub-layers, and the electrolyte solution
sub-layers and the electroactive polymer sub-layers are alternately
arranged, wherein M is a positive integer.
[0010] According to some embodiments of the present disclosure, the
electroactive polymer layer comprises an ion-type electroactive
polymer and is doped with a movable anion.
[0011] According to some embodiments of the present disclosure, the
flexible unit further comprises a first insulating layer overlaying
the thin film transistor, wherein the second electrode is formed on
a side of the first insulating layer away from the thin film
transistor, the first insulating layer is provided with a via hole,
and the source electrode or drain electrode of the thin film
transistor is electrically connected to the second electrode
through the via hole.
[0012] According to some embodiments of the present disclosure, the
flexible unit comprises a thin film transistor array composed of a
plurality of thin film transistors, a second electrode array
composed of a plurality of second electrodes, and one or more first
electrodes. The source electrode or drain electrode of each thin
film transistor in the thin film transistor array is electrically
connected to one respective second electrode in the second
electrode array, and the plurality of second electrodes in the
second electrode array are arranged separately and respectively
corresponding to different positions of the electroactive polymer
layer.
[0013] According to some embodiments of the present disclosure, one
first electrode together with at least two second electrodes
provides an electric field acting on the electroactive polymer
layer.
[0014] According to some embodiments of the present disclosure, the
flexible unit further comprises a data voltage generator configured
to be electrically connected to the source electrodes or drain
electrodes of the plurality of thin film transistors in the thin
film transistor array to provide different first voltages to the
second electrodes.
[0015] According to some embodiments of the present disclosure, the
flexible body comprises a plurality of flexible units arranged
along an extending direction of the electroactive polymer
layer.
[0016] According to some embodiments of the present disclosure, the
first electrode is a common electrode.
[0017] According to some embodiments of the present disclosure, the
flexible body comprises a plurality of flexible units arranged in
lamination in a direction perpendicular to an extending direction
of the electroactive polymer layer.
[0018] According to some embodiments of the present disclosure, the
flexible body is for use in an artificial muscle, an artificial
limb, a massage chair, or a transmitter.
[0019] Other embodiments of the present disclosure provide a method
for controlling the flexible body according to any one of the
preceding embodiments to deform, comprising:
[0020] applying a first voltage to the source electrode or drain
electrode of the thin film transistor;
[0021] applying a second voltage to the first electrode;
[0022] changing the first voltage to modulate the electric field
acting on the electroactive polymer layer, thereby controlling the
flexible body to deform accordingly.
[0023] According to some embodiments of the present disclosure, the
flexible unit comprises a thin film transistor array composed of a
plurality of thin film transistors, a second electrode array
composed of a plurality of second electrodes, one or more first
electrodes, and a data voltage generator electrically connected to
the source electrodes or drain electrodes of the plurality of thin
film transistors in the thin film transistor array, and the method
comprises: providing different first voltages to the plurality of
thin film transistors by the data voltage generator; applying the
second voltage to the one or more first electrodes; changing the
first voltage provided by the data voltage generator to modulate
the electric field acting on the electroactive polymer layer,
thereby controlling the flexible body to deform accordingly.
[0024] According to some embodiments of the present disclosure, the
flexible body comprises a plurality of flexible units, and the
method comprises: providing different first voltages to the thin
film transistors in one respective flexible unit by a plurality of
data voltage generators respectively; applying the second voltage
to the first electrode; changing the first voltages provided by the
plurality of data voltage generators to modulate the electric field
acting on the electroactive polymer layer, thereby controlling the
flexible body to deform accordingly.
BRIEF DESCRIPTION OF DRAWINGS
[0025] FIG. 1 shows a schematic partial section view of a flexible
unit of a flexible body according to an embodiment of the present
disclosure;
[0026] FIG. 2 shows a schematic partial section view of a flexible
unit of a flexible body according to another embodiment of the
present disclosure;
[0027] FIG. 3 shows a schematic partial section view of a flexible
unit of a flexible body according to still another embodiment of
the present disclosure;
[0028] FIG. 4 shows a schematic partial section view of a flexible
unit of a flexible body according to yet another embodiment of the
present disclosure;
[0029] FIG. 5 shows a schematic partial section view of a flexible
unit of a flexible body according to yet another embodiment of the
present disclosure;
[0030] FIG. 6 shows a schematic partial section view of a flexible
unit of a flexible body according to yet another embodiment of the
present disclosure;
[0031] FIG. 7 shows a schematic partial section view of a flexible
body according to an embodiment of the present disclosure; and
[0032] FIG. 8 shows a schematic partial section view of a flexible
body according to another embodiment of the present disclosure.
DETAILED DESCRIPTION
[0033] Particular embodiments of the present disclosure will be
described in detail below by way of examples. It should be
understood that the embodiments of the present disclosure are not
limited to examples set forth below. Those skilled in the art can
change or modify the embodiments by making use of the principle or
spirit of the present disclosure to obtain other embodiments in
different forms which obviously fall within the scope of the
present application.
[0034] FIG. 1 is a schematic partial section view of an example
structure of a flexible unit 100 of a flexible body according to an
embodiment of the present disclosure. Here, the flexible unit 100
comprises a first electrode 11, a second electrode 12, an
electroactive polymer layer 13, and a thin film transistor (T),
wherein a source electrode (s) or a drain electrode (d) of the thin
film transistor (T) is electrically connected to the second
electrode 12. The first electrode 11 and the second electrode 12
are configured to provide an electric field acting on the
electroactive polymer layer 13, and the electroactive polymer layer
13 is configured to deform in response to the electric field
provided by the first electrode 11 and the second electrode 12.
[0035] For the flexible body provided in the embodiments of the
present disclosure, the electroactive polymer layer thereof may
deform under the action of the electric field provided by the first
electrode and the second electrode, and the above-mentioned
electric field may be generated by applying an external voltage to
the first electrode and the second electrode and be controlled by
the external voltage and the thin film transistor. For example,
external voltages with different waveforms can generate electric
fields in different directions or with different intensities
between the first electrode and the second electrode. In addition,
average amplitude of the external voltage can be modulated by
controlling the "On" or "Off" state of the thin film transistor,
thereby allowing the flexible unit to deform as desired, such as to
expand or shrink. Therefore, such a flexible body has a wide
variety of application scenarios. For example, the flexible body
can be applied in a robot as a constituent structure of an
artificial muscle. At this time, flexible stretching and shrinkage
of the artificial muscle can be achieved without any motor or
hydraulic system.
[0036] Therefore, the application of the flexible body can greatly
simplify the structure of the artificial muscle and its control
system, and enhance the stretching and shrinkage flexibility of the
artificial muscle, thereby improving the overall performance of the
robot. Similarly, such a flexible body can also be used in an
artificial limb to improve the flexibility or convenience when user
walks or moves. It can be understood from the above discussion that
the expanding process of the flexible body is actually a process to
convert an electric energy to a mechanical energy. The mechanical
energy has a relatively low intensity and a mild release process,
and the expanding process can provide a mild impact force to an
external object. Therefore, the flexible body can also be applied
in any circumstance in need of such a mild impact force, including,
but not limited to, an electrical massage chair, a transmitter, and
so on.
[0037] In the example of FIG. 1, the flexible unit 100 comprises a
first flexible substrate 10 and a second flexible substrate 20
opposite to each other, wherein the first flexible substrate 10 and
the second flexible substrate 20 can serve as an encapsulating
structure of the flexible unit. The first electrode 11 and the
second electrode 12 are respectively arranged on either side of the
electroactive polymer layer 13. Alternatively, in another
embodiment, as shown in FIG. 2, the first electrode 11 and the
second electrode 12 may be arranged on the same side of the
electroactive polymer layer 13, and the first electrode 11 and the
second electrode 12 may be separated by an insulating layer (for
example, a first insulating layer 17). It can be understood that,
in this case, the electroactive polymer layer 13 will deform under
the action of the electric field generated by the first electrode
11 and the second electrode 12. In these embodiments, all of
different arrangements of the first electrode 11 and the second
electrode 12 allow the first and second electrodes to generate an
electric field acting on the electroactive polymer layer, thereby
enabling deformation of the electroactive polymer layer.
[0038] The electroactive polymer layer 13 may comprise an
electron-type electroactive polymer or an ion-type electroactive
polymer, and the type of the electroactive polymer is not limited
in the present disclosure. In the embodiments where the
electroactive polymer in the electroactive polymer layer is an
ion-type electroactive polymer, the flexible unit 100 further
comprises an electrolyte solution layer in contact with the
ion-type electroactive polymer layer. As shown in FIG. 3, the
flexible unit of the flexible body provided in the embodiments of
the present disclosure comprises: a first flexible substrate 10 and
a second flexible substrate 20 opposite to each other; a first
electrode 11 and a second electrode 12 between the first flexible
substrate 10 and the second flexible substrate 20; an ion-type
electroactive polymer layer 13 between the first electrode and the
second electrode; and an electrolyte solution layer 14 in contact
with the ion-type electroactive polymer layer 13. It can be
understood that, in some embodiments, the flexible body may have no
thin film transistor, and in such embodiments, the flexible units
in the flexible body deform directly in response to the change of
external voltage. Therefore, the term "flexible body" mentioned
herein generally refers to a structure which can deform under the
action of an external voltage and at least comprises a first
electrode, a second electrode and an electroactive polymer layer as
mentioned previously. The ion-type electroactive polymer can be
oxidized under the action of an electric field with a relatively
low intensity. Therefore, in this instance, the expansion and
shrinkage of the flexible body can be achieved at a relatively low
external voltage. The components of the ion-type electroactive
polymer may include, for example, polyaniline, polypyrrole,
polythiophene, and so on. The electrolyte solution in the flexible
body may include, but not limited to, hydrochloric acid, sulfuric
acid, perchloric acid, or sodium chloride solution.
[0039] The deformation process of the flexible unit 100 as shown in
FIG. 3 will be illustrated below. When the flexible body is
electrically connected to a power supply to generate a voltage
difference between the first electrode and the second electrode, an
electric field can be formed between the first electrode and the
second electrode. The electroactive polymer in the electroactive
polymer layer 13 is oxidized under the action of the electric
field, resulting in positive charges on the polymer backbone. In
order to maintain electric neutrality, anions in the electrolyte
solution layer 14 will pass into the electroactive polymer layer to
neutralize the positive charges generated by oxidation. Since all
ions (including anions and cations) in the electrolyte solution
layer 14 are solvated, solvent associated with the anions will also
pass into the electroactive polymer layer together with the anions,
resulting in volume expansion of the electroactive polymer layer
and finally leading to expansion of the whole flexible unit. It can
be understood that the higher the electric field intensity between
the first electrode and the second electrode, the higher the
oxidization degree of the polymer in the electroactive polymer
layer 13 is, and the higher the expansion degree of the flexible
unit is. When the voltage applied to the first electrode and the
second electrode is removed, the polymer in the electroactive
polymer layer 13 is reduced. The reduction is actually an electron
gain process. Then, anions in the electroactive polymer layer 13
are discharged so as to maintain electric neutrality. Likewise,
solvent associated with the anions is also discharged from the
electroactive polymer layer 13 together with the anions. As a
result, the volume of the electroactive polymer layer shrinks, such
that the whole flexible body is in a shrinking state.
[0040] It can be understood that the flexible units 100
schematically shown in FIG. 1 to FIG. 3 are for the convenience of
understanding the deformation process of the flexible unit as
described above, and will not limit the shape or appearance of the
flexible body in any way. The flexible body or the flexible unit
may have corresponding morphology or dimension according to
different application scenarios, which is not limited herein. In
addition, although FIG. 3 shows that the electrolyte solution layer
14 is below the electroactive polymer layer 13, this also will not
limit the protection scope of the present application. The
electrolyte solution layer 14 and the electroactive polymer layer
13 may have any relative position relationship, as long as the
electrolyte solution layer 14 is in contact with the electroactive
polymer layer 13 such that ions in the electrolyte solution can
pass into the electroactive polymer layer.
[0041] Next, reference is made to FIG. 4. According to another
embodiment of the present disclosure, the electroactive polymer
layer comprises a first electroactive polymer sub-layer 131 and a
second electroactive polymer sub-layer 132, and the electrolyte
solution layer 14 is between the first electroactive polymer
sub-layer 131 and the second electroactive polymer sub-layer 132.
In this embodiment, since the electrolyte solution layer is between
the first electroactive polymer sub-layer and the second
electroactive polymer sub-layer, that is, the electrolyte solution
is surrounded by the electroactive polymer, there is a larger
contact area between the electrolyte solution and the electroactive
polymer. When the flexible body receives the external voltage to
work, more ions in the electrolyte solution will pass into the
electroactive polymer layer, thereby achieving a higher degree of
expansion and shrinkage at the same external voltage. This further
increases the flexibility of the device using the flexible body and
facilitates improvement on the energy utilization efficiency.
[0042] Further, in another embodiment, the electroactive polymer
layer may be doped with a movable anion (for example,
ClO.sub.4.sup.- and so on). As such, the conductivity of the
electroactive polymer layer is increased, which is beneficial for
increasing the expansion and shrinkage speed of the flexible body
in response to the external voltage. As a result, the response rate
of the device using the flexible body is facilitated.
[0043] Based on the embodiment as shown in FIG. 4, it can be
understood that, in another embodiment, the electroactive polymer
layer may comprise N electroactive polymer sub-layers, the
electrolyte solution layer may comprise N-1 electrolyte solution
sub-layers, and each electrolyte solution sub-layer is located
between two adjacent electroactive polymer sub-layers, wherein N is
an integer greater than 1. Optionally, in still another embodiment,
the electroactive polymer layer may comprise M electroactive
polymer sub-layers, the electrolyte solution layer may comprise M
or M+1 electrolyte solution sub-layers, and the electrolyte
solution sub-layers and the electroactive polymer sub-layers are
alternately arranged, wherein M is a positive integer. That is, in
some embodiments, the electrolyte solution layer is formed from a
plurality of electrolyte solution sub-layers, the electroactive
polymer layer is formed from a plurality of electroactive polymer
sub-layers, and these electrolyte solution sub-layers and
electroactive polymer sub-layers are alternately arranged. The
upper limits for M and N are not particularly limited, and
generally, M or N may be 50 or less, 20 or less, or 10 or less.
[0044] Referring to FIG. 1 or FIG. 2 again, in some embodiments,
each flexible unit of the flexible body comprises a first
insulating layer 17 overlaying the thin film transistor, and the
second electrode 12 is formed on a side of the first insulating
layer 17 away from the thin film transistor, wherein the first
insulating layer 17 is provided with a via hole, and the source
electrode or drain electrode of the thin film transistor is
electrically connected to the second electrode 12 through the via
hole. FIG. 1 or FIG. 2 also schematically shows the basic structure
of single thin film transistor (T), wherein the thin film
transistor (T) comprises a gate electrode (g), a source electrode
(s), a drain electrode (d), and an active layer (a). The gate
electrode (g) and the active layer (a) may be separated by an
insulating layer, known as a gate insulating layer 18. The second
electrode 12 is electrically connected to one of the source
electrode and drain electrode of the thin film transistor (T) (for
example, the drain electrode (d)), the other of the source
electrode and drain electrode of the thin film transistor (T) may
be electrically connected to an external power supply, and the
first electrode 11 may be electrically connected to a reference
potential. In the example of FIG. 1 or FIG. 2, the source electrode
(s) of the thin film transistor (T) may be used for receiving the
external voltage. Thus, the thin film transistor (T) may be used to
drive the second electrode 12. When the gate electrode (g) of the
thin film transistor receives a corresponding control signal to
turn on the thin film transistor, it can transport the voltage from
the power supply to the second electrode 12, forming an electric
field between the second electrode 12 and the first electrode 11.
The electric field causes the electroactive polymer layer between
these two electrodes to deform. In this embodiment, the first
insulating layer 17 provides a good protection for the thin film
transistor, reducing adverse effect of the potential of the second
electrode on the working performance of the thin film transistor.
The configuration of the via hole in the first insulating layer
enables that the first insulating layer will not influence the
driving effect of the thin film transistor on the second
electrode.
[0045] FIG. 1 or FIG. 2 schematically shows that a single thin film
transistor and a single second electrode 12 are arranged in the
flexible unit. However, in other embodiments, a plurality of thin
film transistors and a plurality of second electrodes may be
arranged. For example, in the embodiment of FIG. 5, the flexible
unit of the flexible body comprises a thin film transistor array
composed of a plurality of thin film transistors, a second
electrode array composed of a plurality of second electrodes 12,
and one or more first electrodes 11. The source electrode or drain
electrode of each thin film transistor in the thin film transistor
array is electrically connected to one respective second electrode
12 in the second electrode array, and the plurality of second
electrodes in the second electrode array are arranged separately
from each other and respectively corresponding to different
positions of the electroactive polymer layer. For the thin film
transistor array herein, a portion of the thin film transistors may
be controlled in an "On" state, and the other portion of the thin
film transistors may be in an "Off" state. That is, the thin film
transistors at different positions may be independently controlled
as desired, such that there is an electric field between a portion
of the second electrodes 12 and the first electrode 11, and there
is no electric field between the other portion of the second
electrodes 12 and the first electrode 11, thereby achieving local
deformation of the flexible body.
[0046] In such embodiments, the electric field acting on the
electroactive polymer layer may be provided by one first electrode
together with at least two second electrodes. In the example shown
in FIG. 5, the thin film transistor array and the second electrode
array are arranged on the second flexible substrate 20, and the
first electrode 11 is arranged on a surface of the first flexible
substrate 10 facing the second flexible substrate 20, and
corresponds to the plurality of second electrodes in the second
electrode array.
[0047] In order to form an electric field between the first
electrode and the second electrode, in some embodiments, a power
conversion device capable of generating a desired voltage may be
provided in the flexible unit. For example, as shown in FIG. 6, in
some embodiments, the flexible unit comprises a data voltage
generator 30 configured to be electrically connected to the source
electrodes or drain electrodes of the thin film transistors in the
thin film transistor array to provide different data voltages (also
referred to as "first voltages" herein) to the second electrodes.
In the example shown in FIG. 6, the data voltage generator 30 is
electrically connected to the source electrode or drain electrode
of the thin film transistor through the via hole, although the data
voltage generator 30 may be electrically connected to the source
electrode or drain electrode of the thin film transistor in other
ways. In addition, for simplicity, FIG. 6 shows that (a partial
structure of) the data voltage generator 30 is arranged in the same
layer as the second electrode, but the arrangement of the data
voltage generator 30 is not limited thereto.
[0048] In such an embodiment, a portion of the thin film
transistors in the thin film transistor array may be controlled in
an "On" state, and the other portion of the thin film transistors
may be in an "Off" state. That is, by independently controlling the
thin film transistors at different positions, it can be enabled
that there is an electric field between a portion of the second
electrodes 12 and the first electrode 11, and there is no electric
field between the other portion of the second electrodes 12 and the
first electrode 11, thereby achieving local deformation of the
flexible body. That is, according to practical requirements, some
regions of the flexible body may be controlled in an expanding
state, and the other regions may be controlled in a shrinking
state, to achieve a desired stretching and shrinking effect.
Furthermore, based on the supply voltage, the data voltage
generator 30 can generate data voltages with different amplitudes,
which are then provided to different thin film transistors and
corresponding second electrodes. Thus, electric fields with
different intensities can be formed between different second
electrodes and the first electrode, finally resulting in different
degrees of expansion in different regions of the flexible body. It
can be understood that the expansion and shrinkage of the flexible
body can be changed continuously according to the gate electrode
control signal of the thin film transistor and the data voltage
provided by the data voltage generator. Therefore, the embodiment
further increases the stretching and shrinking flexibility of the
flexible body, enabling more flexible and fine movement of the
device (for example, robot, massage chair and so on) using the
flexible body.
[0049] As shown in FIG. 5, according to some embodiments of the
present disclosure, the thin film transistor is arranged on the
second flexible substrate 20, the flexible unit further comprises a
first insulating layer 17 overlaying the thin film transistor, and
the second electrode 12 is formed on the first insulating layer 17.
The second electrode 12 may be connected to the drain electrode (d)
of the thin film transistor through the via hole in the first
insulating layer 17. Of course, it can be understood by those
skilled in the art that the gate electrode (g) and the active layer
(a) of the thin film transistor are also separated by an insulating
layer, known as a gate insulating layer 18.
[0050] According to some embodiments of the present disclosure, as
shown in FIG. 5, the first electrode 11 may act as a common
electrode, and the flexible unit may further comprise a common
electrode wire 21 on the second flexible substrate 20, wherein the
common electrode wire 21 is connected to the common electrode 11
through a conductive adhesive 19. Therefore, the common electrode
wire 21 has the same potential (for example, the reference
potential) as the common electrode 11. The common electrode wire 21
may be formed from the same material as the gate electrode (g) of
the thin film transistor by one-step patterning process (i.e., only
using one mask plate). As such, the fabrication efficiency of the
flexible body can be increased, and the production cost can be
reduced.
[0051] In some embodiments, the conductive adhesive 19 is a
carbon-based conductive silicone, for example, a photo-sensitive
carbon-based conductive silicone. The selection of the
photo-sensitive carbon-based conductive silicone is beneficial for
ensuring the reliability of the connection between the first
substrate and the second substrate, and contributes to preventing
the first substrate and the second substrate from separation due to
the stretching and shrinking deformation of the electroactive
polymer layer. In addition, the photo-sensitive carbon-based
conductive silicone can avoid or alleviate evaporation of the
electrolyte solution during packaging of the flexible body.
[0052] According to some embodiments of the present disclosure, the
flexible body comprises a plurality of flexible units, and these
flexible units may be arranged in any suitable mode to meet
different requirements. For example, in the embodiment as shown in
FIG. 7, the flexible units 100 in the flexible body are arranged
along an extending direction of the electroactive polymer layer.
These flexible units 100 may be disposed between two opposite
flexible substrates. Therefore, different controls may be performed
on different flexible units 100 as desired to cause different
deformation. Thus, desired deformation of the whole flexible body
can be achieved.
[0053] Optionally, in another embodiment, as shown in FIG. 8, the
flexible units 100 in the flexible body are arranged in lamination
in a direction perpendicular to an extending direction of the
electroactive polymer layer in the flexible units 100. Adjacent
flexible units 100 may be separated by a flexible material layer.
Since the deformation degree in the direction perpendicular to the
extending direction of the electroactive polymer layer in the
flexible units 100 is greater than the deformation degree along the
extending direction of the electroactive polymer layer at the same
external voltage, less flexible units are arranged in the direction
perpendicular to the extending direction of the electroactive
polymer layer in the flexible units, and desired deformation degree
can also be achieved in that direction, as a result, the
utilization efficiency is improved and the cost is saved. Of
course, in other embodiments, the flexible units 100 in FIG. 8 may
be replaced by the flexible units 100 of the flexible body as shown
in FIG. 7.
[0054] As described previously, the flexible body provided in the
embodiments of the present disclosure can be used as a constituent
structure of an artificial muscle. Therefore, other embodiments of
the present disclosure provide an artificial muscle comprising the
flexible body according to any one of the preceding embodiments.
The artificial muscle using the flexible body provided in the
embodiments of the present disclosure has a simpler structure,
avoids complicated control system, and can achieve more flexible
stretching and shrinking.
[0055] In addition, yet another embodiment of the present
disclosure provides a method for fabricating the flexible body
described in the preceding embodiments, comprising: providing a
rigid substrate; fabricating the flexible body according to the
preceding embodiments on the rigid substrate; and separating the
flexible body from the rigid substrate. As such, the scale
production of the flexible body can be achieved, and the
fabrication efficiency of the flexible body can be improved.
[0056] A particular process for fabricating single flexible unit
will be illustrated below with reference to FIG. 5 again. First, a
gate electrode (g) of the thin film transistor and a common
electrode wire 21 may be fabricated on a second flexible substrate
20 by processes of photoresist applying, exposing, developing,
etching and so on. Then, a gate insulating layer 18, and an active
layer (a) and source/drain electrodes of the thin film transistor
are fabricated sequentially. Next, a first insulating layer 17
overlaying the thin film transistor is fabricated, and a via hole
is formed in the first insulating layer 17. Subsequently, a second
electrode 12 is formed on the first insulating layer 17 by
sputtering a metal material, such that the second electrode 12 is
connected to the source/drain electrode of the thin film transistor
through the via hole in the first insulating layer 17. After the
above steps are completed, or before carrying out the above steps,
the following additional steps may be performed: fabricating a
first electrode 11 sequentially on a first flexible substrate 10,
then applying an electroactive polymer with a thickness on the
first electrode 11, and injecting an electrolyte solution into the
electroactive polymer. At this time, some layer structures have
been respectively fabricated on the first flexible substrate and
the second flexible substrate. Next, the first flexible substrate
and the second flexible substrate are combined in alignment with
each other with a conductive adhesive 19, such that the first
electrode 11 and the common electrode wire 21 are connected through
the conductive adhesive 19, thereby obtaining the flexible body as
shown in FIG. 5. In some embodiments, an organic insulating
material may be used as a material for fabricating the insulating
layer in the above steps, and a coupling agent may be used for
connecting an inorganic material to an organic material. This may
be beneficial for long lasting stability of the layer structures on
the flexible substrate, such that the flexible body has a good
bending deformation stability.
[0057] Other embodiments of the present disclosure provide a method
for controlling a flexible body to deform, wherein the flexible
body may be the flexible body according to any one of the preceding
embodiments. The method may comprise steps of: applying a first
voltage to the source electrode or drain electrode of the thin film
transistor; applying a second voltage to the first electrode;
changing the first voltage to modulate the electric field acting on
the electroactive polymer layer, thereby controlling the flexible
body to deform accordingly.
[0058] Further, in another embodiment, the flexible unit comprises
a thin film transistor array composed of a plurality of thin film
transistors, a second electrode array composed of a plurality of
second electrodes, one or more first electrodes, and a data voltage
generator electrically connected to the source electrodes or drain
electrodes of the plurality of thin film transistors in the thin
film transistor array, and the method for controlling the flexible
body to deform comprises: providing different first voltages to the
thin film transistors by the data voltage generator; applying the
second voltage to the first electrode; changing the first voltage
provided by the data voltage generator to modulate the electric
field acting on the electroactive polymer layer, thereby
controlling the flexible body to deform accordingly.
[0059] According to some embodiments of the present disclosure, the
flexible body comprises a plurality of flexible units, and the
method for controlling the flexible body to deform comprises:
providing different first voltages to the thin film transistors in
one respective flexible unit by a plurality of data voltage
generators respectively; applying the second voltage to the first
electrode; changing the first voltages provided by the plurality of
data voltage generators to modulate the electric field acting on
the electroactive polymer layer, thereby controlling the flexible
body to deform accordingly.
[0060] Although some exemplary embodiments of the present
application have been specifically described above, other
variations of the embodiments can be appreciated and achieved by
those skilled in the art when implementing the claimed invention,
according to the investigation on the drawings, the disclosure and
the claims. In the claims, the word "comprise" does not exclude the
presence of other elements, and each claim does not limit the
number of the technical features as recited therein. Although some
features are recited in different dependent claims, the present
application is intended to cover embodiments in which these
features are combined together.
* * * * *